1. Field of the Invention
This invention relates in general to wheeled vehicles such as bicycles. In particular, this invention relates to the assembly of an apparatus for the primary fastening of a wheel axle to a wheel mount using a manual rotational tightening. This invention does not propose any secondary retention which may or may not be used in conjunction with the primary fastening system disclosed herein.
2. Description of Prior Art
Prior art for manually operated wheel fastening systems consists mostly of a variety of eccentric cam operated quick release levers. A drawbar is mounted concentrically inside a hollow hub axle and the quick release cam is mounted on one end, and the adjusting nut on the other end. The quick release cam, when locked, pulls the drawbar outward thereby pushing inward against the dropout as well as causing the adjusting nut to push inward on the opposite dropout. In this way, the wheel mounts are clamped between the quick release cam and the hub on one side of the hub, and between the adjusting nut and the hub on the other side of the hub thereby fastening the wheel.
In most cases, the wheel mounts, or dropouts, are configured with a recessed surface, or a set of safety tabs, such that the operation of the cam quick release on its own is not sufficient to allow for wheel removal. Therefore when re-installing the wheel, the operator must perform the iterative process of locating the adjusting nut in the exact position for correct cam operation using rotation, then operating the eccentric cam by flipping the lever over the top of the cam in a different orientation from the rotation to finally fasten the wheel.
This process is not fully understood by many operators. Most operators can understand a cam lever that needs to flip over the top for locking. Likewise, most operators can understand simply rotating a lever until tight. However, the combination of the two is often not done properly and can lead to unwanted wheel separation.
It would therefore be preferable to allow for wheel removal by the simple operation of a quick release cam with no re-adjusting required of the adjusting nut as set forth in U.S. Published document 2007/0052286 (Montague). Separately, it would also be preferable to allow for wheel removal by the simple rotation of a lever or knob until tight.
There are several examples of prior art where the operation of the eccentric cam is the only method needed to fasten the wheel. There have been very few systems which are simply manually turned to tighten for locking.
U.S. Pat. No. 6,089,675 (Schlanger) discloses an invention wherein the wheel is attached to a more traditional slotted wheel mount on one side and a unique threaded hole on the other wheel mount. Also shown are a variety of knob or lever operated fastening systems where the wheel is fastened by, in most cases, rotating a lever or knob until tight. Embodiments shown generally have a knob or lever on one side of the wheel, and the bicycle frame or fork on the other side is threaded to accept a threaded drawbar. In several embodiments, a nut is used which is mounted to the dropout in a rotationally fixed manner. Most embodiments require the use of a non-traditional fork for correct function of the primary locking system. Furthermore, in the locked position, the lever or knob is never adjustable to a specific orientation (such as parallel to a fork blade) as is common on today's bicycles. This adjustable orientation is important for a lever as passing branches and other objects may catch on a forward facing lever. Schlanger generally outlines the method of attachment of the wheel to the bike while the invention disclosed herein generally outlines the method of attachment between a turn handle and the drawbar.
U.S. Pat. No. 4,079,958 (Segawa) discloses an invention using a wing nut which is threaded onto a drawbar and the system is operated by rotation of the wing nut. The drawbar is threaded at both ends and an adjusting nut is mounted on the opposite end. While the invention disclosed herein outlines a method of fastening the handle or distal nut relative to the drawbar in a rotationally-fixed manner, Segawa does not fix any element rotationally to the drawbar.
As used herein, the term “drawbar” is also known in the industry as a “skewer”, “spindle”, “connecting rod”, “control shaft” and “retaining rod”. Also the word “handle” is used to denote a variety of “levers”, “knobs”, and “wing nuts”.